Liquid-tight container, preform, method for producing same, and uses

Abstract

The present invention relates to a liquid-tight container comprising a container wall which surrounds a container interior at least in part, wherein: a jacket element and a first end element are connected to one another and each form a portion of the container wall; wherein the jacket element delimits the container interior in a transverse direction extending from the inside to the outside in relation to the container interior, and comprises a rim portion having a first edge; wherein the first end element delimits the container interior at a first end of the liquid-tight container in a longitudinal direction extending along the length of the container, and comprises a further edge which points in the longitudinal direction; wherein the rim portion a. is located at the first end of the container, and b. encloses the further edge counter to the transverse direction from the outside to the inside in such a way that i. the first edge of the jacket element points counter to the longitudinal direction, and ii. the liquid-tight container comprises, at the first end in the transverse direction, a ply sequence comprising A. a first ply of the jacket element, B. a ply of the first end element, and C. a further ply of the jacket element; wherein the rim portion comprises, at least on a side pointing inwards counter to the transverse direction, a plurality of portions of a first type and a plurality of portions of a further type, which portions differ from one another in their thickness in the transverse direction. The invention also relates to a precursor for producing the liquid-tight container, to a method for producing a liquid-tight container, to the use of a liquid-tight container, and to the use of an ultrasonic generator and/or an ultrasonic sonotrode.

1 . A liquid-tight container, comprising a container wall which surrounds a container interior at least in part;
 wherein a jacket element and a first end element are connected to one another and each form a portion of the container wall;   wherein the jacket element
 delimits the container interior in a transverse direction extending from the inside to the outside in relation to the container interior, and 
 comprises a rim portion having a first edge; 
   wherein the first end element
 delimits the container interior at a first end of the liquid-tight container in a longitudinal direction extending along the length of the liquid-tight container, and 
 comprises a further edge which points in the longitudinal direction; 
   wherein the rim portion   a. is located at the first end of the liquid-tight container, and   b. encloses the further edge counter to the transverse direction from the outside to the inside in such a way that
 i. the first edge of the jacket element points counter to the longitudinal direction, and 
 ii. the liquid-tight container comprises, at the first end in the transverse direction, a ply sequence comprising 
 A. a first ply of the jacket element, 
 B. a ply of the first end element, and 
 C. a further ply of the jacket element; 
   wherein the rim portion comprises, at least on an inward-facing side counter to the transverse direction, a plurality of portions of a first type and a plurality of portions of a further type;   wherein the portions of the first type and the portions of the further type follow one another in a circumferential direction that extends along the further edge;   wherein the first ply of the jacket element has a thickness in the transverse direction;   wherein the thickness of the first ply is a mathematical function of a position along the circumferential direction;   wherein the mathematical function has a plurality of local maxima and a plurality of local minima;   wherein each portion of the first type comprises exactly one of the local maxima and each portion of the further type comprises exactly one of the local minima;   wherein the thickness of the first ply in each entire portion of the first type is at least 0.7 times a value of the local maximum comprised by the respective portion of the first type;   wherein the thickness of the first ply in each entire portion of the further type is at most 1.3 times a value of the local minimum comprised by the respective portion of the further type;   wherein each portion of the first type has a first length in the circumferential direction;   wherein each portion of the further type has a second length in the circumferential direction;   characterized in that each second length is at least 10% of each first length.   
     
     
         2 . The liquid-tight container according to  claim 1 , wherein the value of each local minimum is 10 to 80% of the value of each local maximum. 
     
     
         3 . The liquid-tight container according to  claim 1 , wherein the further edge forms a closed curve with a third length along the circumferential direction;
 wherein the first end element has a height extending in the longitudinal direction at each point of the closed curve;   wherein the rim portion protrudes beyond the further edge at each point of the closed curve such that the rim portion extends from the further edge to the first edge by an overhang length;   wherein the overhang length is measured on a side of the rim portion facing away from the first end element;   wherein the overhang length along at least 50% of the third length is 30 to 100% of the height.   
     
     
         4 . The liquid-tight container according to  claim 1 , wherein the jacket element is at least partially formed from a first sheet-like material. 
     
     
         5 . The liquid-tight container according to  claim 4 , wherein the first sheet-like material is a first sheet-like composite comprising a first layer sequence;
 wherein the first layer sequence comprises a first carrier layer.   
     
     
         6 . The liquid-tight container according to  claim 4 , wherein the first carrier layer in the first layer sequence is overlaid with a first polymer inner layer on a side facing the container interior. 
     
     
         7 . The liquid-tight container according to  claim 5 , wherein the first carrier layer in the first layer sequence is overlaid with a first polymer outer layer on a side facing away from the container interior. 
     
     
         8 . The liquid-tight container according to  claim 7 , wherein the first layer sequence between the first carrier layer and the first polymer inner layer comprises a first barrier layer. 
     
     
         9 . A precursor for producing the liquid-tight container according to  claim 1 , the precursor comprising a container wall which surrounds the container interior at least in part;
 wherein the jacket element and the first end element are connected to one another and each form a portion of the container wall;   wherein the jacket element
 delimits the container interior in the transverse direction, and 
 comprises the rim portion having the first edge; 
   wherein the first end element
 delimits the container interior at a first end of the precursor in the longitudinal direction, and 
 comprises the further edge; 
   wherein the rim portion is arranged at the first end of the precursor;   wherein the first edge and the further edge point in the longitudinal direction;   wherein the further edge forms a closed curve with a third length;   wherein the first end element has a height extending in the longitudinal direction at each point of the closed curve;   wherein the rim portion protrudes beyond the further edge at each point of the closed curve such that the rim portion extends from the further edge to the first edge by an overhang length;   wherein the overhang length is measured on a side of the rim portion facing away from the first end element;   wherein the overhang length along at least 50% of the third length is 30 to 100% of the height.   
     
     
         10 . A method for producing a liquid-tight container, the method comprising as process steps
 a. providing a precursor of the liquid-tight container, the precursor comprising a container wall at least partially surrounding a container interior;
 wherein a jacket element and a first end element are connected to one another and each form a portion of the container wall; 
 wherein the jacket element
 delimits the container interior in a transverse direction extending from the inside to the outside in relation to the container interior, and 
 comprises a rim portion having a first edge; 
 
 wherein the first end element
 delimits the container interior at a first end of the precursor in a longitudinal direction extending along a length of the precursor, and 
 comprises a further edge; 
 
 wherein the rim portion is arranged at the first end of the precursor; 
 wherein the first edge and the further edge point in the longitudinal direction; 
   b. forming the rim portion by contacting it with a forming tool, so that the rim portion encloses the further edge counter to the transverse direction from the outside to the inside in such a way that
 i. the first edge of the jacket element points opposite to the longitudinal direction, and 
 ii. the precursor or the liquid-tight container obtained therefrom has at the first end in the transverse direction a layer sequence comprising
 A. a first ply of the jacket element, 
 B. a ply of the first end element, and 
 C. a further ply of the jacket element; 
 
 characterized in that the forming tool carries out an oscillation with a frequency in a range from 15 to 50 kHz during the forming. 
   
     
     
         11 . The method according to  claim 10 , wherein the oscillation takes place in a direction that forms an angle of less than 30° with the longitudinal direction and counter to this direction. 
     
     
         12 . The method according to  claim 10 , wherein the forming tool is set into oscillation before contacting the rim portion. 
     
     
         13 . A use of the liquid-tight container according to  claim 1  for storing or transporting a liquid. 
     
     
         14 . A use of a sheet-like composite for producing the liquid-tight container according to  claim 1 ;
 wherein the jacket element or the first end element or both are at least partially formed from the sheet-like composite.   
     
     
         15 . A use
 a) of an ultrasonic generator to excite the oscillation, or   b) of an ultrasonic sonotrode as the forming tool,   c) or a) and b)   each in the method according to  claim 10 .